As far as the cost goes... Cinemax was $8-$10 when there was just one Cinemax channel. When they started having more, I don't remember the channel package price going up sharply... By which I mean... It didn't go from $8-$10 for one channel to $30+ for all of the Cinemax channels.
So... basically people were used to Cinemax costing whatever it cost and you get whatever channel you get. The fact that Cinemax themselves doesn't make a bigger deal of this is telling, to me... I never see Cinemax commercials, for example, saying "leave Dish because they won't carry Cinemax 12" or whatever channel...
Viacom, Disney, AMC, etc. had disputes and negotiations and they always want Dish to carry all of their channels... especially when they launch a new one... But I honestly can't remember the company (Cinemax) or Dish or even subscribers making a big stink at any point over any of the missing premiums.
People would scream if Dish dropped the whole Cinemax suite I expect... but no issues with some channels being missing... and more to the point Cinemax keeps being ok not trying to get Dish to carry those missing channels.
It's very weird to me in light of how almost all the other contracts go for channels.